140 The Study of Animal Life part h 



The birds cover their eggs with their wings. The butterfly 

 lays hers where the grubs will find their food. The star- 

 fish cast theirs adrift in the sea. The same story is true 

 of the flowers. They are the nursing mothers. In their 

 heart the young plant grows until the first leaves appear ; 

 not till then does it drop away, and not without food 

 prepared and placed ready for use — enclosed in what we 

 call the seed. But the seaweed, like the star-fish that 

 crawls upon it, allows its young seeds quite unformed to be 

 floated away by the tide. 



All seeds, then, are parts of the living matter of the 

 parent ; some leave naked and without food ; others are 

 protected by shells or by husks which are filled with food ; 

 others live within the mother until they have ceased really 

 to be seeds, and are fully formed new creatures. 



Now the living matter of any simple organism is so much 

 the same throughout the whole body that almost any part 

 of it will do to build the new generation from. Thus, 

 although the sea-anemone does sometimes set apart certain 

 cells as seeds, yet any part of the body will, if cut off, grow 

 into a complete creature. The same thing is true of a moss 

 plant. But the more highly organised animals have their 

 living matter set to such different service in their various 

 organs that most of it does not keep all the qualities of the 

 whole creature, but only of that part to which it belongs. 

 Thus if a starfish lose its arm, another will grow from the 

 stump. A snail can in this way repeatedly regrow its horns. 

 Even so highly developed an animal as a lizard can grow a 

 new tail. With ourselves this power is confined to growing 

 new skin if we lose part of it, or mending a bone if it be 

 broken, and other similar processes. 



When we clearly understand in what way the offspring 

 of all creatures arise from their parents, how they are, as 

 Erasmus Darwin said long ago, like separated buds, then 

 we see the truth of the often-made comparison between any 

 or all species of animals and an organism. The individuals 

 of a species are not indeed bound together by protoplasmic 

 strands, but their interdependence is not less complete. A 

 single species utterly destroyed might modify the life of the 



